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South-western Victorian Blackfish (Gadopsis cv.)

The South-western Victorian Blackfish, also called Yiritja or South-west River Blackfish, is a medium-sized, non-migratory native fish found only in south-western Victoria. It occurs in small, isolated populations in the Hopkins River and Portland Coast catchments, so works near suitable waterways need careful planning, fish protection and water-quality controls. It is listed as Endangered under the Commonwealth EPBC Act and is considered Critically Endangered in Victoria.

Conservation status

Commonwealth, EPBC Act 1999: Endangered.

Breeding season

The breeding season of the South-western Victorian Blackfish is not established. As a small, isolated, non-migratory freshwater fish, activity and breeding may vary between catchments and with flow, water quality and habitat condition.

Breeding mode: Not recorded.

Breeding sites: Not recorded. The species uses dense in-stream cover, but specific spawning or nesting sites are unknown.

Clutch or litter size: Not recorded.

Incubation period: Not recorded.

Young and development: Not recorded. The duration of any dependent or early life stages is unknown.

Breeding frequency and maturity: Not recorded.

Activity, breeding and risk may change between years and between the three known isolated populations, particularly after fire, low flows, storms or changes in water quality.

  • Resident activity and habitat use: The South-western Victorian Blackfish is non-migratory and may use suitable lower to mid reach habitat throughout the year.
  • Possible breeding and spawning activity: Breeding months are not established, so works should allow for possible breeding activity in any month.
  • Young and early life stages: The timing and habitat of young fish are unknown, so dense in-stream cover should be retained year-round.
  • Low dissolved oxygen, sediment and debris risk: Monitor waterways in every month, with extra care after fire, storms, earthworks or runoff events.
  • Highest clearing risk: Treat all months as high risk for works in occupied waterways because breeding timing and young fish habitat are poorly known.

Identification: Appearance and identification

Yiritja is a native freshwater fish in the genus Gadopsis. It has only recently been recognised as a valid taxon and is awaiting formal description, so field identification should be confirmed by an experienced freshwater fish ecologist.

Yiritja is a medium-sized, non-migratory blackfish. Reliable diagnostic features, colour descriptions, measurements and identification keys are not yet established for field use.

Treat any Gadopsis blackfish captured in south-western Victorian waterways as potentially Yiritja until it has been identified by a suitably experienced specialist.

  • Record the exact capture location, waterway, date, habitat and photograph the fish in water where practicable.
  • Use an approved fish handling method and release the fish promptly at the capture site unless a permit or specialist advice requires otherwise.

Identification: Calls and similar species

Yiritja is not known for a distinctive field call, and acoustic detection is not a recognised survey method for this fish.

The eastern lineage, Gippsland Blackfish, is recorded separately as Gadopsis sp. SEV. The available field information does not give diagnostic characters to distinguish the two lineages.

Identification: Field signs

There are no reliable terrestrial signs such as droppings, nests, whitewash, stains or odour to search for. Presence is best established by targeted aquatic survey.

Dense cover in the channel, suitable water quality and a confirmed record nearby should be treated as indicators of potential habitat, even when fish are not observed.

Distribution: Range in Australia

Yiritja is endemic to Victoria and is known from south-western Victoria. Only three small, isolated populations are known, which makes each occupied waterway and connecting habitat significant for project planning.

The known range extends across the Hopkins River and Portland Coast catchments in south-western Victoria.

The Darlots Creek population is the largest of the three known populations. Records and survey work also include Lake Condah and Darlots Creek within the Budj Bim landscape.

  • State: Victoria only.
  • Region: south-western Victoria.
  • Catchments: Hopkins River and Portland Coast.

Distribution: Population pattern

The known populations are small and isolated. The Darlots Creek population was affected by the 2019 to 2020 bushfires.

Surveys between April and October 2020 captured eight healthy Yiritja at one location. These fish covered a good size range similar to earlier surveys, but the result is not an estimate of total population size.

  • Do not assume that a short, unsuccessful survey has demonstrated absence.
  • Check current Victorian biodiversity records and local Traditional Owner knowledge before finalising site access, clearing or waterway works.

Distribution: Overseas range

Yiritja has no known range outside Australia.

Habitat: Waterway setting

Look for Yiritja in freshwater creek and river reaches with permanent or persistent aquatic habitat and plenty of cover within the channel. It is a bottom-dwelling fish that requires higher dissolved oxygen levels than were recorded at some survey locations.

Preferred habitat is in the lower to mid reaches of creeks and rivers. Yiritja can occur in still to flowing water, so both quiet channel margins and flowing sections may need consideration.

On a work site, inspect the full aquatic footprint, including the channel, undercut margins, pools, connected backwaters and areas immediately upstream and downstream of the proposed works.

  • Freshwater creeks and rivers.
  • Lower to mid channel reaches.
  • Still to flowing water.
  • Sites with dense in-stream cover.

Habitat: Cover and channel features

Dense in-stream cover is a defining habitat feature. Retain submerged and partly submerged cover wherever practicable, including natural woody material and complex channel-edge structure.

Avoid unnecessarily simplifying the channel or removing cover during access, bank stabilisation, utility installation and construction near the waterway.

  • Complex channel margins.
  • Covered sections of creek or river.
  • Areas with shade and refuge from direct flow.
  • Connected aquatic habitat upstream and downstream of the site.

Habitat: Water quality

Low dissolved oxygen and high phosphorus have been detected in survey waterways. These conditions can be particularly harmful to Yiritja because it remains near the bottom of the water column and does not move to the surface where oxygen is generally higher.

Use baseline water-quality results and current field measurements to guide work controls. Escalate sudden changes in oxygen, turbidity, temperature or fish behaviour to the project environmental representative.

  • Prevent sediment, ash, concrete washout, fuels and nutrients from entering the waterway.
  • Maintain flow and avoid creating stagnant, isolated pockets.
  • Include a fish-kill response in the project emergency plan.

Foraging habitat: Likely feeding areas

The diet and feeding behaviour of Yiritja are poorly known. For site management, protect the water quality, cover and connected aquatic habitat that support its food resources.

Yiritja is a bottom-dwelling fish associated with dense in-stream cover. Suitable feeding areas are therefore likely to include the channel bed, covered margins and low-flow refuges within the creek or river.

Do not disturb the bed or remove cover unless the activity has been assessed and approved under the relevant permit and environmental controls.

  • Covered channel margins.
  • Areas with stable bed and bank structure.
  • Low-flow areas connected to the main channel.
  • Reach-scale habitat upstream and downstream of the work area.

Foraging habitat: Managing food resources

Fire-related ash, sediment and debris flows can clog streams and affect in-stream food and habitat availability. Excess phosphorus and other pollutants can also alter aquatic conditions.

Keep disturbed soil out of drainage lines and stage earthworks so exposed areas are stabilised before rainfall.

  • Install and maintain sediment and erosion controls before breaking ground.
  • Inspect controls after rainfall and repair failures promptly.
  • Prevent spoil, mulch and construction materials from entering the channel.

Breeding habitat: Potential breeding habitat

Specific breeding sites, spawning behaviour and breeding timing have not been established for Yiritja. Because the species occurs in very small populations, treat all suitable occupied habitat as potentially important for breeding.

Retain dense in-stream cover and stable channel margins throughout the work area. Avoid removing or isolating habitat that could be used for spawning, sheltering eggs or supporting young fish.

Maintain aquatic connectivity during construction. A temporary barrier, dewatered section or sediment plug can remove access to suitable habitat even when the main channel remains intact.

  • Dense submerged or partly submerged cover.
  • Stable channel margins and bed features.
  • Connected freshwater habitat.
  • Areas with adequate dissolved oxygen.

Breeding habitat: Timing and work planning

A breeding season has not been established, so do not rely on a seasonal timing window to avoid impacts. Plan in-water works around the lowest-risk conditions identified by the project fish ecologist and relevant authorities.

Complete fish rescue and relocation planning before any isolation, dewatering or diversion of the channel. Work must be undertaken under the appropriate Victorian Fisheries Authority requirements and permits.

  • Survey before disturbing aquatic habitat.
  • Use a staged, supervised dewatering process where dewatering is authorised.
  • Keep an incident and fish-handling record for all aquatic works.

Sheltering habitat: Shelter features to retain

Yiritja shelters in dense in-stream cover and remains close to the bottom of the waterway. Protect refuge habitat during clearing, bank works, crossings and temporary waterway diversions.

Look for complex cover within the channel and along the water's edge. The available field information does not identify one preferred shelter structure, so retain a range of natural cover rather than selecting only one feature type.

Avoid removing woody material, undercut edges and other stable cover unless removal is necessary, authorised and offset by an ecologically appropriate design.

  • Dense in-stream cover.
  • Covered channel edges.
  • Stable bed and bank features.
  • Connected pools and low-flow refuges.

Sheltering habitat: Construction controls

Keep machinery, stockpiles, access tracks and temporary compounds out of the channel and immediate riparian area where practicable. Prevent vibration, sediment and debris from filling refuge areas.

If fish are present during isolation or dewatering, stop and follow the approved fish rescue procedure. Do not capture or move Yiritja without the required authority and experienced supervision.

  • Fence and clearly mark aquatic exclusion zones.
  • Use clean waterway crossings and minimise the time of temporary occupation.
  • Inspect downstream refuge habitat during and after works.

Threats: Sediment, ash and altered flows

Yiritja is rapidly declining in range and abundance and is highly sensitive to changes in aquatic habitat and water quality. Development controls should be scaled to its Endangered Commonwealth listing, Critically Endangered Victorian assessment and very small number of known populations.

Clearing, earthworks, road crossings and bank disturbance can wash sediment into waterways. Post-fire ash, sediment and debris flows can clog streams, smother habitat and reduce food availability.

Prevent runoff from entering the channel and retain vegetated buffers and stable banks wherever possible. Do not place spoil, fill or cleared vegetation where it can enter flood flows.

  • Stage clearing and earthworks.
  • Stabilise exposed soil before forecast rainfall.
  • Use sediment controls suited to the size and flow of the waterway.
  • Inspect controls during and after rainfall.

Threats: Low dissolved oxygen and poor water quality

Repeated low dissolved oxygen and high phosphorus have been detected in relevant waterways. Construction can worsen these conditions through stagnant diversions, organic loads, nutrient runoff, dewatering and accidental releases.

Measure baseline conditions where required, maintain through-flow, and respond quickly to fish distress or a fish kill. Include water-quality triggers and escalation contacts in the site environmental plan.

  • Prevent fuel, chemicals, concrete washout and nutrients from entering the waterway.
  • Avoid isolating fish in shallow or stagnant water.
  • Keep emergency aeration, containment and fish-rescue arrangements clear to the site team.

Threats: Introduced fish

Redfin and Tench have been captured in survey waterways. They are large, predatory introduced species that affect waterway ecology and may add pressure to small blackfish populations.

Do not move live fish, water, mud or aquatic equipment between catchments. Clean, dry and inspect equipment between waterways in accordance with the project biosecurity procedure.

  • Use separate clean equipment for separate waterways where practicable.
  • Report unusual fish concentrations, fish kills or suspected new pest populations.
  • Do not release captured fish or bait into the waterway.

Threats: Fire and direct site disturbance

The 2019 to 2020 fires affected the largest known population at Darlots Creek and also affected banks around Lake Condah. Fire can increase water temperature, ash and sediment inputs, debris flows and habitat loss.

Plan post-fire works with extra care around unstable banks and recently burned catchments. Before works begin, check whether the site is within or connected to known Yiritja habitat and confirm current approval and referral requirements under Commonwealth and Victorian law.

  • Retain surviving riparian vegetation and channel cover.
  • Avoid unnecessary access through burned banks and waterways.
  • Use Gunditjmara-led survey and management input where the project occurs in the Budj Bim landscape or other areas of cultural significance.
  • Report confirmed captures and significant habitat impacts through the project fauna and biodiversity reporting process.

Survey methodology: 1. Desktop assessment

Yiritja is a small-range, endangered freshwater fish that is difficult to detect without targeted aquatic sampling. Use a qualified aquatic ecologist and obtain the required fisheries permissions before sampling.

Map all waterways, wetlands and connected drainage lines within and downstream of the project area.

Give particular attention to lower to mid reaches of creeks and rivers in the Hopkins River and Portland Coast catchments.

Identify dense in-stream cover, still to flowing water, refuge habitat, recent fire impacts, sediment sources and sites with poor water quality.

Consult Gunditjmara Traditional Owners and relevant Victorian biodiversity and fisheries agencies before finalising survey locations.

  • Treat all suitable habitat as potentially occupied where records are limited or absent.
  • Review recent records, fire history, water-quality results and proposed works that could alter flow, cover or dissolved oxygen.

Survey methodology: 2. Targeted aquatic survey

Use fyke nets and other approved fish-sampling methods suited to the waterway. A suitably experienced aquatic ecologist should select the method, net placement and effort for each site.

Use fish-friendly equipment and check nets at intervals set by the permit and site conditions. Reduce soak time or suspend sampling if fish are stressed, water quality deteriorates or temperatures rise.

Consider complementary methods such as baited traps, visual searches and environmental DNA where they are approved and appropriate. Confirm any suspected Yiritja record with an experienced fish taxonomist.

  • Survey representative habitat, including dense cover, pools, slow-flowing margins and connected reaches.
  • Sample both occupied-looking habitat and areas that may be affected downstream by the works.
  • Use culturally informed methods and protocols where working in the Budj Bim landscape.

Survey methodology: 3. Timing and conditions

The species is non-migratory, but seasonal activity and breeding timing are poorly known. Plan surveys across suitable seasons where the risk or consequence of disturbance is high, rather than relying on a single visit.

Budj Bim surveys recorded Yiritja from April to October 2020. Use this period as a practical starting point for survey planning, while recognising that detection will vary with flow, temperature and water quality.

Avoid sampling during fish kills, very low dissolved oxygen, extreme temperatures, flood flows or immediately after heavy sediment movement.

  • Record recent rainfall, flow conditions, water temperature, dissolved oxygen, turbidity and phosphorus where practicable.
  • Repeat surveys when initial results may have been affected by poor conditions or low detectability.

Survey methodology: 4. Records and identification

Record the date, time, weather, flow, water quality, coordinates, waterway, habitat type, net locations, soak time, number of checks and total effort.

For every fish, record identification, length where permitted, condition, sex if apparent, photographs and release location. Record bycatch, introduced Redfin and Tench, and any fish mortality.

Keep voucher material only where authorised. Do not rely on the synonym Gadopsis marmoratus alone when assessing records, because Yiritja is recognised as a distinct taxon awaiting formal description.

  • Map each capture and suspected detection separately.
  • Report positive records promptly to the project ecologist, regulator and relevant Traditional Owner organisation.
  • Maintain chain of custody for photographs, samples and electronic data.

Before habitat disturbance: 1. Approvals and permits

Avoid disturbing occupied waterways wherever possible. Because Yiritja is listed as Endangered and only three small, isolated populations are known, plan works around retaining habitat, water quality and aquatic connectivity.

Screen the action under the Environment Protection and Biodiversity Conservation Act 1999. Seek an EPBC referral or other Commonwealth advice where the action may significantly affect Yiritja or its habitat.

In Victoria, obtain the required Victorian Fisheries Authority research, collection, handling and relocation permissions before aquatic survey or fish movement. Confirm any planning, waterway, threatened species and land management approvals.

A Queensland species management program is not a pathway for this Victorian-endemic fish. If a project is proposed in Queensland, confirm the species identification and relevant protected wildlife requirements with the Queensland regulator before relying on a listing or management program.

  • Confirm permit conditions, approved personnel, reporting deadlines and release requirements in writing.
  • Check whether works require approvals for bed or bank disturbance, waterway crossings, dewatering, sediment discharge or changes to flow.
  • Engage Gunditjmara Traditional Owners early for projects in their Country and incorporate agreed cultural protocols.

Before habitat disturbance: 2. Avoidance and site design

Retain waterways, dense in-stream cover, undercut banks and connected refuge habitat. Avoid channel realignment, unnecessary bed disturbance, clearing of streamside vegetation and removal of woody or rocky cover.

Keep works, stockpiles, access tracks, fuels and sediment controls out of the waterway where practicable. Prevent low dissolved oxygen water, nutrients, ash, sediment and contaminated runoff from entering habitat.

Protect upstream and downstream connectivity. Do not isolate fish in a dry or poorly oxygenated reach during staging or dewatering.

  • Use existing access points and previously disturbed areas.
  • Design crossings to maintain natural flow and fish passage.
  • Treat Darlots Creek, Lake Condah and other known or suspected occupied sites as high-risk locations requiring project-specific advice.

Before habitat disturbance: 3. Pre-clearance aquatic survey

Complete a targeted aquatic survey before dewatering, in-stream construction, bank works or removal of aquatic cover. Survey the work area and any reach that could receive changed flows, sediment or poor-quality water.

Use a pre-clearance inspection immediately before works where fish may have moved into temporary pools, isolated channels or refuges since the main survey.

If Yiritja is detected, stop finalising the work method until the aquatic ecologist confirms the permit-compliant response and the regulator is consulted where required.

  • Inspect for live fish, fish kills, low dissolved oxygen, sediment deposits, debris blockage and introduced fish.
  • Set out no-go areas on plans and in the field.
  • Mark exclusion areas clearly and brief all crews before mobilisation.

Before habitat disturbance: 4. Work timing and controls

There is no established Yiritja breeding or migration calendar. Obtain site-specific ecological advice before setting work dates, and avoid periods of poor water quality, extreme heat, fish kills, flood flows and post-fire sediment movement.

Use isolated work zones, cofferdams, screened pumps and clean diversion water only where approved and designed by a qualified aquatic specialist.

Set project-specific buffers around occupied habitat. The buffer should reflect flow, bank stability, sediment risk, noise and the likelihood of changes to dissolved oxygen, rather than using an untested generic distance.

  • Prepare a dewatering and fish rescue plan before work starts.
  • Install and maintain sediment, erosion, nutrient and water-quality controls before breaking ground.
  • Include stop-work triggers for fish distress, mortality, unexpected habitat loss, turbid discharge and low dissolved oxygen.

Before habitat disturbance: 5. Induction and equipment

Induct all workers on Yiritja identification, its Endangered status, aquatic hygiene, exclusion areas and stop-work procedures.

Authorise only trained and permitted personnel to capture, handle, identify or relocate fish.

Clean and disinfect nets, boots, pumps and other equipment between waterways to reduce disease and pest transfer.

  • Provide crews with a site map showing waterways, exclusion zones, access routes and emergency contacts.
  • Keep spill kits, screens, aerated holding containers and suitable transport equipment ready where fish rescue is authorised.
  • Prohibit unauthorised collection, fishing or release of captured fish.

During habitat disturbance: 1. Sequential clearing and isolation

Use a staged, aquatic-fauna-led method for any work that may affect Yiritja habitat. The spotter catcher or aquatic fauna supervisor must have authority to stop work and must use the approved response whenever a fish or affected habitat is found.

Clear from the least sensitive area towards the retained habitat, using small work fronts. Complete terrestrial and bank works before entering the channel where practicable.

Isolate and inspect each work section before dewatering or removing cover. Keep rescued fish in suitable, oxygenated water for the shortest practical time.

Maintain flow and prevent untreated discharge to occupied or connected habitat.

  • Remove debris, vegetation and sediment only under the approved method statement.
  • Use screens on pump intakes and check them regularly.
  • Stop work if isolation fails, water quality declines or fish move into the work zone.

During habitat disturbance: 2. Spotter catcher authority

Give the aquatic fauna supervisor authority to stop machinery, redirect workers and require additional controls. No supervisor should be pressured to continue where permit conditions or animal welfare are at risk.

The supervisor should inspect the channel, margins, cover and retained pools during each stage of work.

Record all stop-work events, the trigger, the response and the person who authorised recommencement.

  • Use radio or direct communication with the site manager and environmental representative.
  • Recommence only after the supervisor confirms that the approved control is in place.
  • Escalate unresolved risks to the regulator and project approval holder.

During habitat disturbance: 3. Fish handling and breeding places

Handle Yiritja only by authorised, trained personnel using methods specified in the permit. Keep handling time short, support the fish properly and maintain water temperature and oxygen conditions.

If an active breeding place, suspected nest, spawning site or fish aggregation is found, stop work in the area. Protect the site, prevent entry and obtain advice from the aquatic ecologist and relevant regulator before proceeding.

Yiritja is a fish and is not expected to use a colony, roost, nest box or bat roost. If another fauna species or a protected breeding place is found, apply that species' stop-work procedure.

  • Do not move fish between catchments or release them at an unapproved site.
  • Do not disturb cover that may contain eggs or sheltering fish until the approved ecologist has assessed it.
  • Follow permit requirements for holding, identification, release and mortality.

During habitat disturbance: 4. Injured fish and fish kills

Remove injured fish from immediate danger only when authorised and when safe to do so. Place the fish in clean, oxygenated water and seek advice from the aquatic fauna supervisor or aquatic veterinarian.

Report fish kills, repeated distress, gasping, unusual behaviour, low dissolved oxygen or sudden water-quality change immediately. Preserve evidence and avoid unnecessary handling.

Do not release distressed fish into water that has poor oxygen, high sediment or suspected contamination.

  • Photograph affected fish and conditions before moving them where practicable.
  • Collect water-quality readings and samples under the incident plan.
  • Notify the project manager, permit holder and relevant regulator according to approval conditions.

During habitat disturbance: 5. Daily records

Record work locations, dates, personnel, equipment, habitat removed, water-quality results, fish captured, handling events, relocations, mortalities, escapes and incidents.

Record the release location and condition of every relocated fish where relocation is authorised.

Keep records with the environmental hold-point documentation and provide them to the project ecologist for reporting.

  • Use consistent animal identification and location codes.
  • Attach photographs, maps, permit references and calibration details for water-quality equipment.
  • Report any Yiritja detection or mortality promptly, not only in the final project report.

After habitat disturbance: 1. Immediate post-clearance check

Post-clearance work should confirm that no fish remain stranded and that retained habitat is functioning. Monitoring should be scaled to the Endangered listing, the small number of known populations and the level of residual risk.

Inspect the full work area, isolated pools, pump lines, diversion channels, downstream margins and debris accumulations after each work stage.

Search for stranded, injured or dead fish and check that screens, barriers and sediment controls are secure.

Continue checks after refilling or reconnection to confirm that fish passage is open and flow is safe.

  • Remove temporary structures only after the aquatic fauna supervisor approves.
  • Check for trapped fish behind cofferdams, in shallow depressions and around pump intakes.
  • Record negative checks as well as captures and mortalities.

After habitat disturbance: 2. Relocated animals

Confirm that every relocated fish reached the approved release site and was released in suitable habitat with adequate cover and oxygenated water.

Where permitted, monitor the release area for delayed mortality, abnormal behaviour or displacement after reconnection.

Do not assume that survival has occurred because fish were released successfully.

  • Use the release method and location specified in the permit or relocation plan.
  • Record release time, condition, water temperature, dissolved oxygen, location and any identifying mark or sample.
  • Report delayed deaths or unexpected movement to the permit holder and regulator.

After habitat disturbance: 3. Post-work monitoring

Use repeat aquatic surveys and water-quality checks at occupied or potentially affected sites. Compare results with pre-work conditions and nearby reference habitat.

Monitor dissolved oxygen, temperature, turbidity, phosphorus, flow, sediment deposition, in-stream cover and fish detections.

Set the duration and frequency through the approval, risk assessment and advice from the aquatic ecologist. Increase monitoring after fire, major rainfall, fish kills or poor water-quality results.

  • Include upstream, work-site and downstream locations where impacts may travel.
  • Use the same methods and effort where comparison is needed.
  • Continue monitoring until habitat controls are stable and agreed performance outcomes are met.

After habitat disturbance: 4. Reporting and incident review

Provide permit, EPBC and state reports within the required timeframes. Include survey effort, detections, mortalities, relocations, habitat changes, water quality, incidents and corrective actions.

Review every stop-work event, fish mortality, failed exclusion, sediment release and unexpected Yiritja detection with the construction team and ecologist.

Update the method statement, induction and emergency plan before the next work stage.

  • Share confirmed records with the relevant Victorian biodiversity database and responsible agencies where required.
  • Discuss outcomes with Gunditjmara Traditional Owners for work on their Country.
  • Retain maps, photographs, field sheets, laboratory results and permit correspondence.

Rehabilitation actions: 1. Waterway and cover restoration

Rehabilitation should restore functioning freshwater habitat, not just the channel outline. For Yiritja, focus on clean, well-oxygenated water, dense in-stream cover, stable banks and connected refuge habitat.

Reinstate natural channel form, flow paths and connected pools where works have altered them. Retain or replace dense in-stream cover using locally appropriate woody material, rocks and aquatic or riparian vegetation under aquatic ecologist advice.

Stabilise banks with methods that reduce erosion and avoid smothering the bed with sediment. Remove temporary barriers, excess spoil and construction debris.

Do not place material where it blocks fish passage, creates unsafe low-oxygen pools or increases flood and debris risk.

  • Use local provenance plants where revegetation is appropriate.
  • Restore shaded margins and stable undercut refuge areas where they were removed.
  • Inspect cover after high flows and repair only under the approved method.

Rehabilitation actions: 2. Water quality and weeds

Prevent sediment, ash, nutrients, hydrocarbons, concrete washout and other pollutants from entering waterways. Maintain erosion and sediment controls until the site is stable.

Manage weeds without introducing herbicide or other contaminants to occupied water. Use aquatic-safe products and application methods where treatment is approved.

Track dissolved oxygen, temperature, turbidity and phosphorus where construction or fire-related impacts remain possible.

  • Keep clean water separate from dirty water.
  • Remove contaminated sediment only under a water-quality and disposal plan.
  • Respond quickly to low dissolved oxygen, fish distress, algal growth or fish kills.

Rehabilitation actions: 3. Lighting, flow and future works

Avoid unnecessary night lighting over waterways and use shielded, warm lighting directed away from the channel where lighting is required.

Design culverts, crossings, pumping systems and scour protection to maintain aquatic connectivity and suitable flow conditions.

Prevent future maintenance access, mowing, spraying or bank works from removing restored cover or discharging sediment.

  • Include Yiritja habitat constraints in the site environmental management plan and asset maintenance schedule.
  • Keep stockpiles, fuels and access routes away from restored habitat.
  • Inspect restored reaches before maintenance and after major rainfall or fire.

Rehabilitation actions: 4. Replacement structures and habitat features

Do not install nest boxes, bat boxes, artificial nest sites or roost structures for Yiritja. These structures do not match the known habitat of this freshwater, bottom-dwelling fish.

Where suitable, replace lost aquatic refuge with approved in-stream cover, stable bank features and connected pools. Confirm the design with an aquatic ecologist before installation.

If another species requires a breeding or roost structure, design and monitor it for that species rather than treating it as Yiritja habitat.

  • Use replacement habitat only where it will remain oxygenated and connected during expected conditions.
  • Avoid creating stagnant artificial pools or debris that can trap fish.
  • Record the location, design, installation date and maintenance requirements of each habitat feature.

Rehabilitation actions: 5. Long-term monitoring

Monitor restored habitat for vegetation establishment, bank stability, in-stream cover, sediment accumulation, water quality and Yiritja detections.

Use repeat surveys at the restored site and suitable reference sites where practicable. Continue until the agreed rehabilitation outcomes are demonstrated.

Treat restoration as adaptive management. Modify controls if habitat is drying, silting, losing cover, becoming hypoxic or failing to support aquatic fauna.

  • Include surveys after major storms, bushfire impacts or fish-kill events when safe and permitted.
  • Report new Yiritja records, declines and mortality promptly.
  • Keep Traditional Owners, regulators and land managers involved in reviewing rehabilitation outcomes.

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